Planoqitaph co



om WIivxnmi, or BERNE, swrrznarmvn.

METHOD-fron PRODUCING TRIMMED-sraarzorvi E1 LATrs`` Patenfedot. 14,' e'isi.

Application led. August 19, 1916. Serial No. 115,898.

To all lwhom t may concern Be it known that I, CARL IVINKLER, a citizen of the Swiss Republic, resident at Berne, in the Swiss Republic, have invented a new and useful Improved Method for Producing Trimmed Stereotype-Plates, of which the following is a specification.

According to a known process, stereotype plates are prepared for printing, that is, they are provided with the necessary difference of relief in the lights and shades by applying a make ready to the back of the matrix used for casting the plates. Heretofore these make readies were made by hand, and Ithey were therefore dependent upon the skill of the workman. By my present invention they are produced by mechanical means. This is done by applying color or ink to a clich, printing block, or the like, designed for type printing, or printing in relief, by means of an inking roll or other means and scraping off the color from the projecting surface of the clich, or the like, and leaving the color in the depressions, and by then using said clich or the like to produce a negative impression of the picture or the like on a surface of chalk or other suitable material. This surface is then deepened at the parts not covered by the Acolor or ink by etching or other means. The make ready produced in this way is applied or stuck to the back of the stereotype matrix, whereafter the lead plates are cast in the usual manner.

On the accompanying drawing- Figure l shows the representation of a black rectangle, with two symmetrically arranged white squares;

Fig. 2 shows the negative impression of said rectangle obtained by inking the white portions (in pictures the lights) and leaving the black portions (in pictures shades) without ink, the dotted line therein representing the outline of the black rectangle of Fig.. l;

F ig. 3 is a perspective section through such an impression with exaggerated thickness after the parts not covered with ink in Fig. 2, thus the Iblack portions in Fig. l, are deepened by etching; y y

Fig. 4. shows the application of this etched im ression to the back of a matrix;

ig. 5 shows the matrix placed ina mold fox-.casting curved platos, after a plate has been cast. The latter two operations are done in the very well known manner as for instance shown also by Patent No. 885,948.

Referring to the drawing, A represents a clicheJ or printing block'having a black rectangle a. andV white squares o; B is the negative produced from A; C is the impression produced from the negative; D is a matrix to which the impression is applied; and E is a curved mold with the matrix therein. From a comparison of` Figs. l and 2 it will be seen that the white and blackportion of the one figure are reversed in the other, and this result is obtained by inking the whit-e portion Z) of Fig. l, while leaving the black portion a without any color, and then making an impression of the clich or the like on a chalk or other suitable surface which can lbe etched. By the etching process the parts not inked, thus the part of the chalk impression corresponding with the black portion (in pictures with the shades) of Fig.` l is deepened as shown in Fig.r 3, and this etching is attached to the back of a matrix, as shown in Fig. 4. It is evident that the parts of the matrix corresponding with the black portion of Fig. l will have less hold during the casting process and it will therefore be bulged in somewhat, thus producing a projecting part of the plate cast.

By this improvement the iinest shades are -caused to influence the degree of relief of the matrix and these differences are transferred to the plates cast.

What I claim and desire to secure by Letters Patent of the United States is:

1. The'improved method of producing a make ready for application to the back of a Y' matrix in casting stereotype plates, which consists in coloring the depressions landelevations of a printing block for raised o r' type printing, removing said color from the ele-I 'I vations ofthe surface lof the block whileA leaving it in the depressionsLmaking an impression of said printing block on a suitable surface',l and in deepeningthe parts of the impression not .covered by color, substantially as set forth.

, 2. The improved method of producing make ready for application to the back of a matrix in casting stereotype plates, which 'consists coloring the,. depressions and elevations of a printing block fr raised or type printing, removing said color from the elenaine to this specification in the presence of Vationsof the surface While leaving itin two subscribing Witnesses..

the depressions nifl-king .aniimpres'sin of l said printing block on a chalk mass, andin CARL WINKLER 5 etching the parts of the impression not cov- Witnesses: Y Y

ered by color, substantially as set forth. O. AUERBAGH,

In testimony YWhereo have signed myv W. J. VSTEHLXSS;V

Copies of this patent may be obtained for ve cents each, by addressing the "Commissioner of Patents,

Y Washington, D. C. 

